Electric-conductor-securing means



Sept. 4, 1923. T. C. RUSSELL ELECTRIC counuc'ron SECURING MEANS Filed Nov. 23, 1922 m K7 w W .Z. p

GfN VENTOR. BY 7 Patented Sept. 4, 1923.

UNITED STATES rnormsc. IwssELL, or cincaeo, ILLINOIS.

,ELE CTBIC-GONDUCTOR-SECUBING MEANS.

Application filed November 23, 1922. Serial No. 602,912.

To all whom it may concern:

Be it known that I, THOMAS C. RUSSELL, a citizen of the United States, and a resident v of Chicago, in the county of Cook and State bof Illinois, haveinvented certain new and useful Improvements in Electric-Conductor-Securing Means, of which the following is a specification.

My invention relates to electric conductor securing means, particularly improved means for securin the resistance conductors on hot plates orming part of electrical heating devices. Such resistance conductors, usually in the form of wire helices, are arranged in grooves provided in the supporting base. These conductors must be kept at the bottom of the grooves to keep them away from any metallic part, such as cook ing utensils, which may be supported on or above the base. The conductors in helix form should also be anchored at intervals to prevent their turns from short circuiting. The main object of my invention is therefore to provide simple fastening means preferably in the form of wire clips or staples which can be readily applied around the resistance wireand then inserted and automatically locked in suitable holes provided in the supporting base.

My invention will be fully understood by reference to the accompanying drawing, in which I Fig. 1 is a plan view of a section of a supporting base, Fig. 2 is a sectional view on plane 22, Fig. 1, 1

Fig. 3 is an enlarged view of one of the clips,

Fig. 4 is an enlarged sectional view show-' 4Q ing the manner of applying the clip, and

" Fig. 5 is an enlarged sectional new showin the clip in anchoring position.

' an the drawing 10 represents a radial section of a circular base or plate of electrical insulating and heat resisting material. Such base has the grooves or channels 11 in which is laid the resistance wire preferably in the form of a helix 12. Vessels or objects to be heated may be applied directly on the base over the resistance wire or a metallic grid (not shown) may be placed over the base for supporting the vessels or objects to be heated. To 1 prevent short circuiting of the helix it must be kept at the bottom of the grooves and away from the vessel or grid on the base, and the helix must also be kept expanded sufliciently to prevent short circuiting of adjacent turns and thus reduction of the electrical efiiciency. The important object of my invention is to provide simple means which can be readily applied to properly anchor the helix at the bottom of the channels, and which will permit the helix to be readily removed in case it is burnt out and renewal is necessary.

My improved anchoring'means is in the form of a wire clip designated as a whole C. The clip is of hairpin or staple shape, being formed from a length of spring wire which is bent intermediate its ends to form the resistance wire receiving loop 13 and the spring legs 14 and 15, these legs a distance below the loop being deflected outwardly to form opposite abutment shoulders 16 and 17. At the desired anchorage points the base 10 has the small holes 18 extending downwardly from the bottom of the channels 11, which holes are in register with the assageways 19 of larger diameter extending upwardly from the bottom of the base. The clips when formed have the shape shown in Fig. 3, the loop being open and the legs 14 and 15'being separated a distance so that the width of the shoulders is greater than the diameter of the holes 18. When a clip is to be applied (Fig. 4) it is first passed around the wire of the helix over the corresponding hole 18 and the limbs 14 and 15 are-then brought together by a'suitable instrument and inserted in the hole 18. The clip is then pressed downwardly and the shoulders 16 and 17 will be brought together as they-travel through the restricted hole 18. When the shoulders have arrived below the hole 18 and in the passageway 19 of larger diameter the legs 14 and 15 will spring apart to normal position and the shoulders will then be wider than the hole 18 and will engage the annular ledge or abutment 20 at the juncture of the passageway 19 and hole 18 (Figs. 2 and 5). The clip will then be anchored and will securely hold the helix at that point against the bottom of the channel 11. The clips are sucessively applied to the helix at desired points until the entire resistance member is securely anchored to the base. The clips are of simple and inexpensive construction and the process of anchoring the resistance element to the base requires very little labor while at the same time the resistance helix 110 can then'be readily removed from the resistance wire.

Having described my invention I claim as follows:

1. The combination with an electrical conductor of a supporting base therefor, said base having a clip receiving hole therein of restricted inlet diameter, and a hairpin shaped spring clip having shoulders normally' apart, said clip receiving said conductor at its bend, said shoulders being forced together during'passage of the cli through the restricted inlet to said hole and springing apart when below said restricted inlet to anchor said conductor to said base.

2. The combination with an electrical conductor of a supporting base therefor, said base having a restricted hole extcndin downwardly a distance from the top an havin a passageway of increased diameter exten ing toward said hole from the bottom of said base whereby to form an abutment led e, a hairpin shapedsprin clip receiving said conductor at its bend and having shoulders in its sides adapted to spring together to permit the clip to pass through said restricted hole and to expand in sald passageway to then engage against said abutment ridge to thereby anchor said conductor to said base.

3. The combination with a supporting base having a channel in its upper side, a resistance conductor in the bottom of said channel, there being holes of reduced diameter extending downwardly in said base from the bottom oi said channel and passageways of increased diameter extend- "111g upwardly to meet said holes from the bottom of said base, there being abutment ridges at the junctures of said holes and passageways, and hairpin shaped spring clips receiving said conductors in their bends and having abutment shoulders engaging against said abutment ridges to anchor said conductor in said channel.

4. The combination of a supporting base havin a channel in its upper side, a resistance elix in said channel, there bein small holes extending downwardly in sai base from the bottom of said channel and pasageways of increased diameter extending-upwardly to meet said holes from the bottom of said base to thereby form abutment ridges below said holes, and hairpin shaped spring clips receiving said helix wire in their bends and extended into said holes and passageways, the legs of each clip being deflected below the bend to form shoulders, said shoulders being brought together during passage of a clip through the corresponding hole and being sprung apart to engage below the respective abutment ridge to thus anchor the helix to the bottom of the channel.

5. The combination with a supporting base having a channel in its upper side, a resistance wire helix in said channel, a passageway extending through said base from the bottom of said channel and having a restricted inlet end, and a hairpin shaped spring clip for receiving the helix wire in its bend and having abutment shoulders in its legs below said bend for engaging with the passageway walls below the restricted inlet to thereby anchor said helix in said channel.

In witness whereof, I hereunto subscribe my name this 17 da of Nov. A. D., 1922.

THOhIAS C. RUSSELL. 

